Tear-open strips for packages



1965 HANS-JURGEN SCHMlT-OHLHOFF TEAR-OPEN STRIPS FOR PACKAGES Filed Dec. 5, 1965 United States Patent 3,217,969 TEAR-OPEN STRIPS FOR PACKAGES Hans-Jurgen Schmit-Ohlhoif, 53 Alfredstrasse, Hamburg, Germany Filed Dec. 5, 1963, Ser. No. 328,340 3 Claims. (Cl. 22951) This is a continuation-in-part of application Serial No. 111,844 filed May 22, 1961, now abandoned.

The invention relates to tear-open packages, particularly those made of material which tears badly.

With such packages, for example outer wraps for packing a plurality of individual cigarette packets, it is either difiicult or impossible to tear the package open by means of a tearing strip cemented externally in the usual fashion. The tear-open strip on such package is therefore cemented to the inside of the package, and during tearing its tongue is grasped to tear out the track of material disposed outside it.

In order to tear the track satisfactorily out of the packing material with this arrangement, it has already been proposed to arrange reinforcing strips on the outside of the package on both sides of the tear-open strip fixed to the underside, the interposed strip of packing being torn out along the edge of the said reinforcing strips, and a sharp cutting edge being formed. It is also known to perforate the packing material itself on both sides of the tear-open strip to facilitate separation of the track disposed between the perforations. However, this cannot be used for air-tight packages.

Another known proposal is the provision of reinforcing strips on both sides of the tear-open strip on the inside of the package, but this requires the application of three strips and is therefore a relatively complicated and costly operation.

The present invention provides a tear-open strip for package comprising an elongated tear-resistant region and regions of lower tear resistance on either side thereof, the tear resistant region having a plurality of tear resistant threads extending lengthwise of the strip and which are loosely cemented together. There is accordingly very little resistance to separation of the tear-open strip from the regions of lower tear resistance on both sides thereof.

In order to prevent the loose thread structure from becoming corrugated or compressed during processing it is coated on at least one side with glue. The coating is effected after the thread structure has left a supply reel and immediately prior to its application to the package, and is sufiicient to prevent such deformations without impairing the tearing properties. The coating in addition makes the strip fluid-tight and non-porous as is often desired for fluid-tight packages. The coating of glue may, for example, consist of hide glue, dextrin glue or other suitable quick-drying material.

In a further development of the invention the strip may be covered with a tearable lining whereby when the package is torn by the tear open strip the surrounding portions of the package are held together by the lining but can be readily separated by tearing the lining. When the strip is torn it comes away from the lining.

A suitable cementing material is chosen for the lining so that the package is thus still held together by the lining which is cemented on both sides of the strip, and can then be pulled apart by hand at any desired subsequent time.

Preferred embodiments of tear-open strips in accordance with the invention are shown by way of illustration 3,217,969 Patented Nov. 16, 1965 ice in the accompanying drawings, wherein the strips being shown cemented to the package:

FIGURE 1 shows a strip with a coating of hide glue applied only to the side lying against the package;

FIGURE 1a is an enlarged fragmentary view clearly showing the prolongation of the filaments which comprise the median portion of the tearing strip; and

FIGURE 2 shows a strip having a lining of tissue paper. The tissue paper is glued to the package on both sides of the strip so that when the package is torn with the tearopen strip it remains held together by the tissue paper.

Referring to FIGURE 1 there is shown a package generally indicated by reference numeral 10, wherein a strip 12, formed of fibers, arranged substantially parallel to one another, is adhesively secured to the inner surface 14 of the package. The strip 12 can very satisfactorily be comprised of long strands or filaments of glass fibers which have excellent tensile strength characteristic and are resistant to being torn. Manifestly, fibers of other materials, either natural or synthetic, may be used in making up the strip 12. The strip 12 is cemented or otherwise adhered to the inner surface 14 by any suitable adhesive such as a hide glue, for example.

The strip 12 is applied in such a manner that one end of the strip is exposed as indicated at 16 to form a gripping tongue. Typically, the median portion of the gripping tongue 16 is manually grasped and pulled to eifectuate the opening of the package 10. Since only the median portion of the strip 12 is actually removed, the filaments or fibers which form the marginal edge portion of the strip 12 remain and form a zone of relatively high strength adjacent the portion. of the package which has been removed.

To facilitate the removal of the median portion of the strip 12, the leading edge thereof is prolongated as illustrated in FIG. la. It will be appreciated that the prolongated portion 16' may be readily grasped by ones fingers, thereby facilitating the opening of the associated package.

FIGURE 2 illustrates an embodiment of the invention wherein a package generally indicated by reference numeral 20 is provided with a strip 22 formed of substantially parallelly arranged fibers of the same general type as illustrated and described in FIGURES 1 and la. The strip 22 is disposed on and secured thereto by the inner surface 24 of the package by a strip 28 of tissue paper or the like. The fiber strip 22 is applied such that one end thereof is exposed to form a gripping tongue 26. The gripping tongue 26 is manually grasped and pulled to effectuate the initial stage in the opening procedure. When the strip 22 and its associate portion of the material which forms the package 20 are removed, the tissue paper strip 28 holds the two sections of the main package together. These two sections may be readily separated since the material of the strip 28 is easily severed.

The advantages of the tear-open strip according to the invention are especially apparent when it. is used in conjunction with a package material which tears badly or is not oriented. The properties of the strip may be adapted to those of the package material by imparting suitable values to the differences between longitudinal and transverse resistance to tearing.

What I claim is:

1. A package consisting of a relatively strong sheet material, said package being provided with a tearing strip on the inside of said sheet material of the package, said tearing strip consisting of a plurality of tear resistant filaments arranged substantially parallel to one another and extending lengthwise of said strip, the median portion only of the filaments being prolongated to form a gripping tongue, and adhesive means for adhering said tearing strip on the inside of said sheet material, so that when said gripping tongue and its associated filaments of said strip are removed, the filaments of the marginal edges of said strip will remain and lend reinforcement to the package in the areas thereof adjacent the portion removed by said gripping tongue and said associated filaments of said tearing strip.

2. The invention according to claim 1 wherein the innermost surface of said tearing strip is covered with a tearable lining whereby when said sheet material of the package is torn by said tearing strip the surrounding portions of the package are held together by said lining but can be readily separated by tearing the lining.

3. The invention according to claim 2 wherein said tearable lining is tissue paper.

References Cited by the Examiner UNITED STATES PATENTS 900,953 10/1908 Reber 22951 X 1,032,026 7/1912 Roden 22951 2,005,665 6/1935 Sagmier 22951 2,120,629 6/ 1938 Schiinemann 22951 2,307,735 1/ 1943 Feher 22951 2,870,953 1/ 1959 Parker et al 22951 2,981,455 4/1961 Cope 22951 X FOREIGN PATENTS 604,965 11/ 1934 Germany.

FRANKLIN T. GARRETT, Primary Examiner. 

1. A PACKAGE CONSISTING OF A RELATIVELY STRONG SHEET MATERIAL, SAID PACKAGE BEING PROVIDED WITH A TEARING STRIP ON THE INSIDE OF SAID SHEET MATERIAL OF THE PACKAGE, SAID TEARING STRIP CONSISTING OF A PLURALITY OF REAR RESISTANT FILAMENTS ARRANGED SUBSTANTIALLY PARALLEL TO ONE ANOTHER AND EXTENDING LENGTHWISE OF SAID STRIP, THE MEDIAN PORTION ONLY OF THE FILAMENTS BEING PROLONGATED TO FORM A GRIPPING TONGUE, AND ADHESIVE MEANS FOR ADHERING SAID TEARING STRIP ON THE INSIDE OF SAID SHEET MATERIAL, SO THAT WHEN SAID GRIPPING TONGUE AND ITS ASSOCIATED FILAMENTS OF SAID STRIP ARE REMOVED, THE FILAMENTS OF THE MARGINAL EDGES OF SAID STRIP WILL REMAIN AND LEAD REINFORCEMENT TO THE PACKAGE IN THE AREAS THEREOF ADJACENT THE PORTION REMOVED BY SAID GRIPPING TONGUE AND SAID ASSOCIATED FILAMENTS OF SAID TEARING STRIP. 